WANG Ming-lei 1,2, LIU Yu-ting2, ZHANG Fu-dong2, LI Jun2, YANG Shen2, SHAO Li-yan2
(1. College of Petroleum Engineering, China University of Petroleum(Beijing), Beijing 102249, China;
2. Research Institute of Petroleum Exploration and Development, Langfang 065007, China)
Abstract: Responding to tight oil reservoir characteristics of the Ordos Basin, using the world's leading micro-nano grade CT scanning, field emission scanning electron microscope and the constant pressure technology, a systematic research on the microstructure characteristics of reservoir pore and throat, pore-throat allocation relation and interstitial material was conducted, and the quantitative analysis data were obtain. Results suggests that size of pores decides the reservoir capacity of tight oil reservoir. Average radius of pores is from 0.5µm to 10µm. The size of throats is the main restricted factor for the development limit. Throats size ranges between 0.3µm and 0.9µm. Low permeability reservoir has high pore throat ratio. Throat restricts the movement of the fluid in pore, and greatly reduces the reservoir transporting ability. Pore interstitial material content is high and dominated by illite. Illite particle has small size and strong plastic characteristics, and its hydration expansion easily leads to pore plugging makes reservoir permeability decreased and reduces the transporting ability of pore.
Keywords: Tight oil reservoir, reservoir microscopic characteristic, pore-throat structure, the Ordos Basin
Email: wml69@petrochina.com.cn
ACTA MINERALOGICA SINICA Vol. 35, No. 3, 2015, Page 318-322
